Improved machine for drilling metals



G. C. TXAFT,

Drilling Metals.

Patented Feb. .1, 1370.

N. PETERS. Phaw-Lilbogmpnf. Washinglun, D C

@leitet glitters @sind @Mita GEORGE O. TAFT, OF WORCESTER, MASSACHUSETTS, ASSGN OR TO THOMAS Y H. DODGE,IOF SAME PLACE.

Letters Patent No. 99,495, dated February l, 1870.

IMPRQVED MAHINE FOR DRILLINC METALS.

The Schedule referred 'to in these Letters Patent: and making part 0f the same.

Talljichom 'it may concern Be it, known that I, GEORGE C. TAFT, of the city and county of Worcester, and Commonwealth of Massachusetts, have invented certain new and useful lmprovements in Drills, of Iwhich the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this specification, in which- Figure 1 represents a side view of my improved drill;

Figure 2 represents a section, on line A B, tig. 4l; and

Figure 3 represents a vertical section through a part of the bed, and the device for holding tbe foot or stand in position.

To enable those skilledin `the art to which my invention belongs, to make and use the same, I will proceed to describe it more in detail.V V

The nature of my invention consists- First, in the combination, with the feed-arm, of an adjustable cam, as will be hereafter explained.

Second, in the combination, with the bed and foot or stand, of a holding-pawl or ratchet-piece, constructed as hereafter described.

r In the drawings- V A is the bed, and B, the head, which niayfbe cast with the bed A, if preferred.

The head B is bored or cored out, and a screw-thread cut therein, to receive the screw-.thread (t upon tbc tubular shaft C, to the outcrend of which the ratchetwheel D is secured.

E is the spindle-head, which is fitted with a recess or socket, in which thedrill is to be inserted, where it is secured by the set-screw b. ,V

The shank lt of the drill-spindle extends through the tubular shaft C, and enters a socket in the innerI end of the lever-piece G, where it is' heid by a setscrew c.

H is a feed-arm, the lower end of which is secured to a stud, (l, which is fitted to roclraud slide in the true of the hole in the cam-piece J which works in a4 slot, K, in the feed-arm H.

L is an adjnstableflever, which is secured to the lever-piece G, by a set-screw, f.

From the foregoing description, it will be seen,that

as the lever L is turned, the drill-spindle F will 4also he turned, while a rocking motion will be imparted tothe feed-arm H, in consequence of the revolution of the cam-piece J yin the slot K, sinceit is eccentric to .the drill-spindle F.

It will be observed, by reference to iig. 2, that Vthe cam-piece J just lls the space between the sides g g of the slot K, and that the sweep of the upper end of the feed-arm H will begreatestwben the cam-piece J is arranged upon the square ende of the lever-piece G, as shown in lig. 2, and that the sweep will be shortcned if the cam-piece J is slipped off, and turned a quarter way around before it is replaced, while, if it is turned half way around, the feed-arm will remain at rest, fthe cani-piece J being then concentric to the ceutrc of the drill-spindleF.

From the foregoing description, it will be seen that the feed can be varied very` readily, by simply turning the cam-piece J ou the many-sided part c, and which part may be made with three, four, or more sides, the hole in the cam-piece being made tov cnn- ,form to the shape of said part c.

' is dropped down, as shown in tig. 3, Athereby holding the foot or stand l) in place during ythe operation of drilling the article or materia', which rests, and is pressed against the front ot' the stand "P,

Vhen it `is desired tomove the stand back or forward,'the cato-hor stop-piece O` can be raised by meansof the thumb-piece Q, a space or recess, m, bcing formedinthe baseof the stand P, to receive the stop-piece O, as fully indicated in fig.-

' 1t will be understood that the lianges n of the stand.

"P are iitted to slide under' the flanges pofthe bed A.

By the use of the stop-device, shown iu the drawings, the stand P can be' adjusted very quickly, while at the same time the objections to the .use of a set screw, to hold the stand in-place, are obvia'ted.

The stop-piece O is made to tit closely in the recess in the base 1t, so that the stand is retained in a very secure and central position.

`ILIaviug described luy improvements in drills,

What I claim therein as new, and of my invent-ion.; and desire to secure by Letters Patent, is-

l. The combination of cam J, having a many-'sided hole formed therein, with a many-sided supportingpiece, c, and the shank or spindle F, said parts being arranged iu relation to each other, substantially as and for the purposes set forth 2. The combination, with the feed-arm H, aud le ver-piece G c, of the cam-piece J, substantially as and for the purposes set forth.

3. The combination, with the standl and bed A., of the stop-piece O Q, said parts being constructed substantially as and for the purposes set forth.

GEO. C. TAFT.

Witnesses:

'.lHos. H. DODGE, ALBERT E. Pansen. 

